The present invention relates to a conventional lock mechanism, for example a door lock, of the kind which incorporates a knob or corresponding device and at least one lock bolt which can be retracted to an unlocking position, by rotating the knob or like device, but with which the locking and unlocking functions of the actual lock mechanism can be activated electrically.
The need of such electrically activated locks has become progressively more apparent in recent times, as a result of the increasing use of electrical lock systems of the kind which are manipulated not with a key, but with a magnetic card provided with coded information or a button array through which a given code number can be inserted, therewith to produce an electric lock-release signal for activation of the lock.
It should be possible to mount such a lock possessing electrically actuable locking and unlocking functions in a conventional manner in a door or the like, and to include a substantially conventional lock case containing the lock bolt, and a conventional knob or corresponding device. In many applications, the lock should be so designed as to enable it to be released from its locking mode from one side of the lock, i.e. from one side of the door, without requiring an electric signal to be produced, i.e. solely by turning the knob or like device. It should also be difficult, of course, to force the lock, and the lock should be constructed so that there is little risk of the lock being damaged if an attempt is made to force the lock from the outside.
The characterizing features of the lock according to the invention are set forth in the accompanying claims.